package com.cws.interceptor;

import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.web.servlet.ModelAndView;
import org.springframework.web.servlet.handler.HandlerInterceptorAdapter;

import com.cws.web.UserSession;


public class CommonInterceptor extends HandlerInterceptorAdapter {
	 private final Logger log = LoggerFactory.getLogger(CommonInterceptor.class);  
	    public static final String LAST_PAGE = "com.alibaba.lastPage";  
	    /* 
	     * 利用正则映射到需要拦截的路径     
	      
	    private String mappingURL; 
	     
	    public void setMappingURL(String mappingURL) {     
	               this.mappingURL = mappingURL;     
	    }    
	  */  
	    /**  
	     * 在业务处理器处理请求之前被调用  
	     * 如果返回false  
	     *     从当前的拦截器往回执行所有拦截器的afterCompletion(),再退出拦截器链 
	     * 如果返回true  
	     *    执行下一个拦截器,直到所有的拦截器都执行完毕  
	     *    再执行被拦截的Controller  
	     *    然后进入拦截器链,  
	     *    从最后一个拦截器往回执行所有的postHandle()  
	     *    接着再从最后一个拦截器往回执行所有的afterCompletion()  
	     */    
	    @Override    
	    public boolean preHandle(HttpServletRequest request,HttpServletResponse response, Object handler) throws Exception {    
	        if ("GET".equalsIgnoreCase(request.getMethod())) {  
	           
	        }  
	        log.info("==============执行顺序: 1、preHandle================");    
	        String requestUri = request.getRequestURI();  
	        String contextPath = request.getContextPath();  
	        String url = requestUri.substring(contextPath.length());  
	        
//	        log.info("requestUri:"+requestUri);    
//	        log.info("contextPath:"+contextPath);    
//	        log.info("url:"+url);    
	          
	        UserSession userSession =  (UserSession)request.getSession().getAttribute(UserSession.USER_SESSION_KEY);   
	        if(userSession == null){  
	            log.info("Interceptor：跳转到login页面！");  
	            request.getRequestDispatcher("/jsp/test.jsp").forward(request, response);  
	            return false;  
	        }  
	            return true;     
	    }    
	    
	    /** 
	     * 在业务处理器处理请求执行完成后,生成视图之前执行的动作    
	     * 可在modelAndView中加入数据，比如当前时间 
	     */  
	    @Override    
	    public void postHandle(HttpServletRequest request,HttpServletResponse response, Object handler,ModelAndView modelAndView) throws Exception {     
	        log.info("==============执行顺序: 2、postHandle================");    
	        if(modelAndView != null){  //加入当前时间    
	            modelAndView.addObject("var", "测试postHandle");    
	        }    
	    }    
	    
	    /**  
	     * 在DispatcherServlet完全处理完请求后被调用,可用于清理资源等   
	     *   
	     * 当有拦截器抛出异常时,会从当前拦截器往回执行所有的拦截器的afterCompletion()  
	     */    
	    @Override    
	    public void afterCompletion(HttpServletRequest request,HttpServletResponse response, Object handler, Exception ex)throws Exception {    
	        log.info("==============执行顺序: 3、afterCompletion================");    
	    }    
}
